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1.
Y. S. Athugala K. M. G. G. Jayasuriya A. M. T. A. Gunarathne C. C. Baskin 《Plant biology (Stuttgart, Germany)》2018,20(5):916-925
- Fruiting season of many Sri Lankan tropical montane species is not synchronised and may not occur when conditions are favourable for seedling establishment. We hypothesised that species with different fruiting seasons have different seed dormancy mechanisms to synchronise timing of germination with a favourable season for establishment. Using six species with different fruiting seasons, we tested this hypothesis.
- Germination and imbibition of intact and manually scarified seeds were studied. Effect of GA3 on germination was examined. Embryo length:seed length (E:S) ratio of freshly matured seeds and of those with a split seed coat was determined. Time taken for radicle and plumule emergence and morphological changes of the embryos were recorded.
- The radicle emerged from Ardisia missionis, Bheza nitidissima and Gaetnera walkeri seeds within 30 days, whereas it took >30 days in other species. Embryos grew in seeds of B. nitidissima and G. walkeri prior to radicle emergence but not in Microtropis wallichiana, Nothapodytes nimmoniana and Symplocos cochinchinensis. A considerable delay was observed between radicle and plumule emergence in all six species. Warm stratification and/or GA3 promoted germination of all species.
- All the tested species have epicotyl dormancy. Seeds of B. nitidissima and G. walkeri have non‐deep simple morphophysiological epicotyl dormancy, and the other four species have non‐deep physiological epicotyl dormancy. Differences in radicle and epicotyl dormancy promote synchronisation of germination to a favourable time for seedling development. Therefore, information on dormancy‐breaking and germination requirements of both radicle and epicotyl are needed to determine the kind of dormancy of a particular species.
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从紫乌头(Aconitum episcopale Levl.)全草中分离出五个二萜生物碱,其中一个为首次从自然界得到,通过光谱分析鉴定为 deacetylbeterophy-lloidine(?),其余四个化合物分别鉴定为 heterophylloidine(?),song-orine(?),talatisamine(?),14-acetyltalatisamine(?),均为首次从该植物中分离得到. 相似文献
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From the root of Aconitum pseudogeniculatum W. T. Wang, collected from the west of Sichuan province, six diterpenoid alkaloids were isolated and identified as denudatine ( Ⅰ ), chasmanine ( Ⅱ ), talatisamine (Ⅲ), yunaconitine (Ⅳ), crassicauline Ⅰ (Ⅴ) and vilmorrinianine C (Ⅵ). Yunaconitine, the major alkaloid of the plant, and its chemically transformed products pseudaconine and tetraacetylpseudaconine, showed antiinflammatory activities. 相似文献
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描述了自陕西省发现的毛莨科乌头属一新种,圆盔乌头（Aconitum rotundocassideum）。由于具有相似的体态和盔形上萼片,此种与特产云南省的粗茎乌头在亲缘上很相近,与后者的区别特征见正文。 相似文献
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描述了自河北省发现的毛茛科乌头属一新种,迁西乌头。此新种在叶和花的形状方面与乌头像似,但其块根二叉状分枝,茎低矮,之字形弯曲,无毛,叶较小,无毛,花单朵顶生,花梗、萼片外面和心片均无毛,而与乌头相区别。 相似文献
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本研究以龙血树柴胡（Bupleurum dracaenoides Huan C.Wang,Z.R.He&H.Sun）的种子为材料,采用不同温度、不同浓度赤霉素、不同化学试剂以及紫外线照射和微波辐射等方式处理后,统计其发芽率、发芽势、发芽指数和发芽时间等指标。结果表明：龙血树柴胡种子萌发最适温度为20℃;100 mg/L的GA3、0.5％的KMnO4和3％的H2O2处理均能促进其种子萌发,但不能使种子萌发和出苗时间提前;25 s微波辐射处理可大幅提高种子发芽率;紫外线照射处理种子0.5 h,萌发效果最佳,但随照射时间的延长对种子萌发则有不同程度的抑制。 相似文献
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Information on seed dormancy is one of the primary requirements for successful seedling propagation of submerged aquatics
and seagrass. Studies on Ruppia
maritima seed germination have been done, but the presence, requirements, and the types of dormancy have not been well understood.
A laboratory study was conducted to understand presence and types of organic dormancy of the seeds of estuarine R. maritima collected from Lake Pontchartrain, Louisiana, USA. Our study results indicate that the brackish estuarine R. maritima population produces seeds that do not have any noticeable initial morphological, physical, and physiological dormancy. Although
dry stratification reduced seed viability and final germination rates, drying seems to induce an earlier germination in R. maritima. Desiccation also appears to induce an environmental dormancy that can be disrupted by exposure to water. Further study on
environmental dormancy is needed to provide information to develop methods for long-term seed storage that can be employed
in greenhouse seedling propagation.
Handling editor: P. Viaroli 相似文献
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On the basis of biosynthsis, distribution of diterpenoid alkaloids aswell as morphological evolution of Chinese species L. (Ranunculaceae), chemotaxonomyof the genus Aconitum is discussed: 1, Subgen. Lycoctonum, containing lycoctonine-type alkaloids and Subgen. Aconitum containing aconitine-type alkaloids, were probably differetiated at the early stageof evolution of the genus Aconitum and evolved respectively in their own ways. 2, In Subgen. Aconitum: (1) Ser. Bullatifolia, containing mainly atisine-, veatchine-type alkaloids, and amino, alcohol and ester base of aconitine-type, and distributed in Hengduan Mountain and Jingsha River valley, where is the centre of moderndifferentiation of species of Aconitum, is probably a series from which Chinese speciesof the genus Aconitum were derived; (2) Ser. Inflata, containing mainly aconitine,mesaconitine and bypaconitine, is an advanced group; (3) Ser. Grsndituberosa, containing mainly aconitine and songorine, is related to Ser. Bulatifolia; (4) Ser. stylosaand Ser. volubilia, containing mainly yunaconitine and other anisyl ester alkaloids formanother advanced branch. 3, Ser. Tangutica and A. naviculare of Ser. Rotaundifolia, containing atisine andlactone-type alkaloids may be a specialized group in high mountains and have occurredat early stage of evolution of the genus Aconitum. 4, Subgen. Gymnaconitum, containing atisine-type alkaloids and amino alcohol ofaconitine type, may als be a specialized group in high mountains. 5, A. franchetii Finet. et Gagnep. mainly containing ester bases of aconitine-typeand closed to A. chasmanthum Stapf, is best placed into Ser. Ambigua. 相似文献
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描述了自陕西省发现的毛茛科乌头属一新种,圆盔乌头（Aconitum rotundocassideum）。由于具有相似的体态和盔形上萼片,此种与特产云南省的粗茎乌头在亲缘上很相近,与后者的区别特征见正文。 相似文献
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WANG WenTsa 《Plant Diversity》2014,36(3):297-300
Two species of the genus Aconitum (Ranunculaceae), Anovoaxillare and Abasitruncatum, are described as new from Xizang Autonomous Region, China. The diagnostic differences between them and their allies are given. 相似文献
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《Animal cells and systems.》2012,16(4):435-438
In the present study, we have examined the crossability of four species in the A. jaluense complex to provide additional information on their delimitation and levels of differentiation. Crosses between diploid A. chiisanense and the tetraploid species including A jaluense s. str., A. triphyllum, and A. pseudoproliferum yielded no fruit‐ or seed‐set, indicating that the former species is reproductively completely isolated from the latter three species. In interspecific crosses between the tetraploid species, combinations involving A. jaluense s. str. resulted in much reduced fruit‐ and seed‐set, indicating that A. jaluense s. str. is more or less reproductively isolated from the other tetraploid species. However, crossing data revealed the absence of reproductive isolation between A. triphyllum and A. pseudoproliferum. These results strongly support the relationships that have been previously suggested for the A. jaluense complex on the basis of morphology, chromosome number, and flavonoid chemistry 相似文献
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研究了西康玉兰(Magnolia wilsonii)种胚的形态大小,温度、层积、硝酸钾、浸种处理和GA_3对种子休眠及萌发的影响.通过将种子脱水至不同含水量和在两种温度(4℃和一20℃)下贮藏100 d后测其生活力,分析各处理对西康玉兰种子活力的影响.结果表明:西康玉兰种子胚尚未分化完全,需经过低温层积完成生理后熟;低温层积和GA3可打破种子休眠.种子最适萌发温度为25/20℃.由此推测,西康玉兰种子具有形态生理休眠特性.西康玉兰种子当含水量降至5.39%,存活率为53.50%.不同含水量的种子贮藏在-20℃条件下,100 d后种子全部死亡;但在4℃下含水量为10.31%的种子存活力高达76%.因此,西康玉兰种子极可能属于中间性种子,其适宜贮藏环境为4℃下的干藏或湿藏. 相似文献
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采用高效液相色谱和薄层色谱对准噶尔乌头中生物碱进行分析,建立了HPLC法测定其中各生物碱含量的方法。结果确定准噶尔乌头中主要含有12-表-欧乌碱、宋果灵、尼奥灵、准噶尔碱和欧乌碱,其中准噶尔碱和欧乌碱为首次在该植物中发现;其疗效与川乌和草乌相近但化学成分差异较大。色谱条件为:Inertsil NH2柱(150 mm×4.6 mm,5μm),流动相正己烷∶乙醇(92∶8),流速1.0 mL/min,检测波长270 nm,进样量10μL。本方法操作简便,结果可靠,重现性好,为准噶尔乌头的质量标准研究提供了实验依据。 相似文献
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Three new aconitine-type C19-diterpenoid alkaloids, richardsonines A-C (1–3), were isolated from the roots of Aconitum richardsonianum Lauener, together with seventeen known compounds (4–20). Their structures were elucidated by extensive spectroscopic analysis, and the absolute stereochemistry of 1 was confirmed by X-ray crystallography. Compounds 2, 5, 8 and 9 were rare C19-diterpenoid alkaloids bearing an OH group at C-16. Isolated compounds were evaluated for inhibition of nitric oxide (NO) production in lipopolysaccharide (LPS)-stimulated neuroinflammatory responses in BV-2 microglial cells. Compounds 3 and 7 showed weak antineuroinflammatory effects with inhibition rates of 35.32 ± 2.29% and 39.94 ± 2.50%, respectively, at a concentration of 100 µM. 相似文献
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Summary Seeds were germinated in soils of known matric potential (ψm) achieved by adding the requisite amount of water to air-dry soil and mixing for several days. The quantity of water was
derived from calibration curves of water content against ψm by use of pressureplate extraction equipment. Soils were transferred to plastic Petri dishes in which seeds were sown. Variations
of the technique permitted germination counting through the transparent dish lid, or by opening the dish and either resealing
or discarding the replicate dish. Measurements of ethylene and carbon dioxide in the soil atmosphere suggest that neither
gas accumulated to a level which could interfere with interpretation of results. Some species showed sensitivity of germination
to water potential which was correlated with the relative wetness of their habitats. 相似文献
20.
毛莨科药用植物种子发芽的研究 总被引：2，自引：0，他引：2
本文报导了不同温度对毛莨科药用植物种子萌发和休眠的影响,提出了不同种的种子发芽的温度范围,发芽适温,发芽所需天数及发芽率,对于中药材生产中掌握不同种的种子发芽适温,确定合适的播种期具有指导意义。 相似文献